TWI779221B - Adhesive composition, adhesive film comprising the same, backplate film comprising adhesive film and plastic organic light emitting display comprising adhesive film - Google Patents

Abstract

The present application relates to an adhesive composition, an adhesive film comprising the same, a backplate film comprising the adhesive film, and a plastic organic light emitting display comprising the adhesive film.

Description

Adhesive composition, adhesive film including same, adhesive film-containing Backplane film and plastic organic light-emitting display

This application claims priority and benefits to Korean Patent Application No. 10-2018-0087772 filed with the Korean Intellectual Property Office on July 27, 2018, the entire contents of which are incorporated herein by reference middle.

This application relates to an adhesive composition, an adhesive film containing it, a backplane film containing the adhesive film, and a plastic organic light emitting display containing the adhesive film.

Adhesive sheets having higher adhesive strength from the onset of adhesion are known in the art. In addition, when using this adhesive sheet to fix the substrate, select an adhesive sheet with sufficient adhesive strength to fix the substrate.

Meanwhile, bubbles generated during the process of bonding the adhesive sheet to the substrate or unexpected foreign substances may be introduced, which are not good in terms of appearance or adhesiveness, and sometimes require re-adhesion of the adhesive sheet. However, such re-adhesion occurs at higher Adhesive strength is difficult in the case of adhesive sheets.

Accordingly, techniques have been devised to reduce such bubbles. For example, techniques have been devised that use embossed liners to form uneven surface shapes on the adhesive surface of pressure-sensitive adhesives. In this case, even when the pressure-sensitive adhesive is bonded to the substrate and air bubbles are mixed into both, the air easily flows out through the surface grooves of the pressure-sensitive adhesive, and thus, the air bubbles are easily removed without re-adhesion. However, the pressure sensitive adhesive described above needs to have some thickness in order to form the grooves. In addition, when this pressure-sensitive adhesive is lightly adhered to the substrate, the adhered area is reduced due to the existence of the groove, and although work such as rework or position renewal is easily performed, sufficient adhesive strength may not be obtained.

In addition, in order to obtain active bending in addition to re-adhesive work, a part of the panel of the plastic organic light emitting diode (POLED) needs to have a process of removing the adhesive sheet, and requires low adhesive strength so that it can be used during the process. A part of the adhesive sheet is removed from the substrate.

However, the general-purpose adhesive sheet has high adhesive strength after being laminated to an adhesive base such as a substrate, and when the adhesive sheet is removed, the panel may be damaged, and in particular, even when not subjected to a specific process during long-term storage. In this case, there is a problem of increased adhesive strength.

Therefore, in view of the above, it has been desired to develop an adhesive sheet in which a low adhesive strength is maintained at the beginning of adhesion and until the process of removing the adhesive sheet even after adhesion to a substrate, and the desired adhesive strength for fixing the substrate is obtained. Adequate adhesive strength.

prior art literature

patent documents

Japanese Patent Application Laid-Open Publication No. 2006-299283

The present application is aimed at providing an adhesive composition, an adhesive film comprising the same, a backplane film comprising the adhesive film, and a plastic organic light emitting display comprising the adhesive film.

An embodiment of the present application provides an adhesive composition comprising a (meth)acrylate resin; and a polymer having a melting temperature (Tm) of 35°C or higher, wherein the polymer is a single Copolymers of functional polysiloxanes with one type of monomer.

Another embodiment provides an adhesive film comprising a base film; and an adhesive sheet comprising the adhesive composition according to an embodiment of the present application or its cured material disposed on one surface of the base film.

Another embodiment provides a backsheet film comprising the adhesive film according to the present application; and a protective film disposed on the base film side of the adhesive film.

Finally, an embodiment of the present application provides a plastic organic light-emitting display, which includes the adhesive film according to the present application; a plastic substrate disposed on the adhesive sheet side of the adhesive film; and an organic light-emitting layer disposed on and in contact with the plastic substrate. On the surface opposite to the surface of the adhesive film.

An adhesive composition according to an embodiment of the present application includes a polymer having a melting temperature (Tm) of 35° C. or higher and a (meth)acrylate resin, and an adhesive sheet including the adhesive composition Low initial adhesion to adhesive substrates Spend.

Specifically, the adhesive sheet included in the adhesive film according to one embodiment of the present application maintains the adhesive strength constant without increasing even when stored at room temperature for a long period of time, although it has low initial adhesive strength with the adhesive base .

Specifically, in order to obtain active bending, a part of the panel of the plastic organic light-emitting diode (POLED) needs to have a process for removing the adhesive sheet, and the backplane film comprising the adhesive sheet according to the present application can maintain a low initial Adhesive strength characteristics to prevent damage to the panel.

101: Basement Membrane

102: Adhesive sheet

103: Adhesive film

104: Protective film

105: back panel film

106:Plastic substrate

107: Organic light-emitting layer

FIG. 1 is a diagram showing a schematic laminated structure of an adhesive film according to one embodiment of the present application.

FIG. 2 is a diagram showing a schematic lamination structure of a backsheet film according to one embodiment of the present application.

FIG. 3 is a diagram illustrating a schematic laminated structure of a plastic organic light emitting display according to an embodiment of the present application.

Figure 4 is a graph presenting a DSC graph of a polymer showing glass transition temperature behavior.

Figure 5 is a graph presenting a DSC graph of a polymer showing melting temperature behavior.

Hereinafter, the specification will be described in more detail.

In this specification, the description that a part "includes" certain components means Other ingredients can be further included and are not excluded unless specifically stated to the contrary.

Embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present disclosure. However, the present disclosure can be implemented in various forms and is not limited to the embodiments described herein.

An embodiment of the present application provides an adhesive composition comprising a (meth)acrylate resin; and a polymer having a melting temperature (Tm) of 35°C or higher, wherein the polymer is a single Copolymers of functional polysiloxanes with one type of monomer.

In addition, an adhesive composition according to an embodiment of the present application may include a curing agent, and an embodiment of the present application provides an adhesive composition including (meth)acrylate resin ; a polymer having a melting temperature (Tm) of 35° C. or higher; and a curing agent, wherein the polymer is a copolymer of a monofunctional polysiloxane and one type of monomer.

Components of polymers included in the adhesive composition can be identified by gas chromatography (GC) analysis, and the components can be identified by nuclear magnetic resonance (NMR) analysis respectively.

Using the adhesive composition comprising a polymer having a melting temperature of 35° C. or higher according to an embodiment of the present application, the adhesive strength of an adhesive sheet prepared subsequently using the adhesive composition remains low. Maintaining low adhesive strength means that there is no difference between the adhesive strength at the beginning and the adhesive strength after a certain time after the adhesive sheet is laminated on the adhesive substrate. The meaning of not having a difference does not mean exactly the same number, and some errors may be included.

Specifically, in order to achieve active bending, plastic OLEDs A part of the panel of (POLED) needs to have a process of removing the adhesive sheet, and the backsheet film including the adhesive sheet according to the present application can prevent damage to the panel by having the characteristic of maintaining low initial adhesive strength.

Melting temperature according to the present application means the temperature at which a material undergoes a phase transition from solid to liquid. Specifically, in the case of a polymer, as the polymer is heated, a marked change in the three-dimensional structure is obtained at a specific temperature, and a change corresponding to the phase transition can be observed, and the temperature can be defined herein as melting temperature.

The melting temperature can be measured using differential scanning calorimetry (DSC). Specifically, the melting temperature is heat absorption and heat generation by absorbing a material generated by phase transition depending on temperature after sealing a sample of approximately 10 mg in a dedicated pan and heating it in a constant temperature rising environment The value measured by the quantity.

In the adhesive composition provided in one embodiment of the present application, the monomer is represented by Chemical Formula 1 below.

In Chemical Formula 1, X is N or O, R ₁ is hydrogen or methyl, and n is an integer of 10 to 30.

In one embodiment of the present application, n in Chemical Formula 1 may be an integer of 10 to 30.

In another embodiment, n of Chemical Formula 1 may be an integer of 15 to 25.

In another embodiment, n in Chemical Formula 1 may be an integer of 16 to 22.

In one embodiment of the present application, X can be N.

In one embodiment of the present application, X can be O.

In Chemical Formula 1, when the value of n is within the above-mentioned range, partial crystallization starts to form due to kinks between carbon side chains, and therefore, a polymer including the carbon side chains can show a melting temperature (Tm )Behavior.

Figure 4 below is a DSC graph of a polymer showing glass transition temperature (Tg) behavior, and Figure 5 below is a DSC graph of a polymer showing melting temperature (Tm) behavior.

As depicted in FIG. 4 , it was recognized that in polymers exhibiting glass transition temperature behavior, a phase transition occurs as the temperature rises slowly in a stable region (glassy state), and a phase transition (glassy state- > rubbery state) emerges slowly over a wide range of temperature intervals. In other words, variable characteristics may appear when polymers exhibiting glass transition temperature behavior are included, however, because the phase transition temperature band is broad, the phase transition partially occurs during long-term storage at room temperature (25°C), This increases the adhesive strength of the adhesive layer, resulting in unfavorable stability over time, and because the phase transition state is rubbery, the variable characteristics may also not be excellent.

As depicted in Figure 5, on the other hand, it is seen that in polymers showing melting temperature behavior, a rapid phase transition (solid -> liquid) occurs at a specific temperature ( melted) appears. In other words, when polymers exhibiting melting temperature behavior are included, a rapid phase transition occurs at a specific temperature value, since the phase transition does not occur at temperatures below the melting temperature, so this can suppress the increase in cohesive strength (over time). excellent stability), and at temperatures above the melting temperature, a phase transition occurs, This results in a rapid increase in adhesive strength (excellent variable characteristics).

The polymer having a melting temperature of 35°C or higher means having a melting temperature of 35°C or higher when monofunctional polysiloxane is copolymerized with one type of monomer represented by Chemical Formula 1 value of the final polymer.

In one embodiment of the present application, the polymer may have a temperature of 35°C or higher, 70°C or lower, preferably 60°C or lower and more preferably 50°C or lower. °C melting temperature.

In one embodiment of the present application, the polymer may have a melting temperature higher than or equal to 35°C and lower than or equal to 44°C.

A copolymer means a material obtained by polymerizing two or more types of different monomers, and in the copolymer, two or more types of monomers may be arranged irregularly or regularly.

Copolymers may include random copolymers with monomers mixed randomly with each other, block copolymers with configured blocks repeated by a certain segment, or alternating copolymers with monomers that repeat and polymerize instead , and the polymer having a melting temperature of 35° C. or higher according to one embodiment of the present application may be a random copolymer, a block copolymer, or an alternating copolymer.

In one embodiment of the present application, the monomer represented by Chemical Formula 1 may be stearyl methacrylate (STMA).

FM-0721 manufactured by Chisso Corporation, KF2012 manufactured by Shin-Etsu Chemical Co., Ltd., or the like can be used as the monofunctional polysilicon according to the present application Oxane, however, monofunctional polysiloxane is not limited thereto.

In one embodiment of the present application, having a melting temperature of 35°C or higher The polymer at 0°C may have a weight average molecular weight of 30,000 g/mole to 200,000 g/mole.

In another embodiment, a polymer having a melting temperature of 35° C. or higher may have a melting temperature of 30,000 g/mol to 150,000 g/mol and preferably 30,000 g/mol to 100,000 g/mol. weight average molecular weight.

When the polymer having a melting temperature of 35° C. or higher according to the present application has a weight average molecular weight value within the above-mentioned range, the molecular configuration in the polymer is excellent, and an adhesive sheet is subsequently produced When the characteristics of low initial adhesive strength are obtained.

The weight-average molecular weight is one of the average molecular weights in which the molecular weight of a certain polymeric material is used as a standard without uniform molecular weight, and is obtained by averaging the molecular weights of the component molecular species of a polymer compound having a molecular weight distribution with a weight fraction The obtained value.

The weight average molecular weight can be measured by gel permeation chromatography (GPC) analysis.

A polymer having a melting temperature of 35° C. or higher comprising a thermal polymerization initiator in a polymer composition comprising a monofunctional polysiloxane; a type of monomer; and solvents.

Toluene may be used as the solvent, however, the solvent is not limited thereto as long as the solvent can dissolve monofunctional polysiloxane and one type of monomer, and such general organic solvents may be used.

In the adhesive composition provided in one example of the present application, having a melting temperature of 35°C or higher based on 100 parts by weight of a polymer having a melting temperature of 35°C or higher of polymers containing a weight greater than or equal to 10 The amount of monofunctional polysiloxane is less than or equal to 40 parts by weight and the monomer is greater than or equal to 60 parts by weight and less than or equal to 90 parts by weight.

In one embodiment of the present application, based on 100 parts by weight of the polymer having a melting temperature of 35° C. or higher than 35° C., the polymer having a melting temperature of 35° C. or higher may contain Equal to 10 parts by weight and less than or equal to 40 parts by weight, preferably greater than or equal to 15 parts by weight and less than or equal to 30 parts by weight, and more preferably greater than or equal to 18 parts by weight and less than or equal to 25 parts by weight of monofunctional Polysiloxane.

In one embodiment of the present application, based on 100 parts by weight of the polymer having a melting temperature of 35° C. or higher than 35° C., the polymer having a melting temperature of 35° C. or higher may contain 60 parts by weight to 90 parts by weight, preferably 65 parts by weight to 85 parts by weight, and more preferably 70 parts by weight to 85 parts by weight .

When the polymer according to the present application having a melting temperature of 35° C. or higher comprises monofunctional polysiloxane and monomers in the above-mentioned parts by weight, the melting temperature value can be properly formed, and thus , and then the initial adhesive strength of the adhesive sheet at room temperature can be kept low.

In the adhesive composition provided in an embodiment of the present application, based on 100 parts by weight of the (meth)acrylate resin, the adhesive composition contains 1 to 10 parts by weight of Or a polymer with a melting temperature above 35°C.

In another embodiment, based on 100 parts by weight of the (meth)acrylate resin, the adhesive composition may contain 1 to 7 parts by weight and preferably 2 to 6 parts by weight of Polymers with a melting temperature of 35°C or higher.

In polymers having a melting temperature of 35°C or higher than mentioned above When included in the adhesive composition in the range of parts by weight, the polymer can be present in an appropriate amount to cause excellent stability over time at room temperature, and thus, the adhesive strength can be maintained constant and subsequently used in plastics When used in organic light-emitting displays, excellent variable performance characteristics are obtained in variable processes.

In one embodiment of the present application, the (meth)acrylate resin may include a (meth)acrylate resin having a weight average molecular weight of 100,000 g/mol to 5,000,000 g/mol.

In this specification, (meth)acrylate means to include both acrylate and methacrylate. Examples of the (meth)acrylate resin may include a copolymer of a (meth)acrylate monomer and a crosslinking functional group-containing monomer.

The (meth)acrylate-based monomer is not particularly limited, however, examples thereof may include alkyl (meth)acrylates, and more specifically, as a monomer having an alkyl group having 1 to 12 carbon atoms, may include pentyl (meth)acrylate, n-butyl (meth)acrylate, ethyl (meth)acrylate, methyl (meth)acrylate, hexyl (meth)acrylate, (meth)acrylate One or two of n-octyl acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate and decyl (meth)acrylate one or more types.

The crosslinking functional group-containing monomer is not particularly limited, however, examples thereof may include one, two or more types of hydroxyl-containing monomers, carboxyl-containing monomers, and nitrogen-containing monomers.

Examples of hydroxyl-containing monomers may include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate ester, 8-hydroxyoctyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, or the like.

Examples of carboxyl-containing monomers may include (meth)acrylic acid, 2-(meth)acryloxyacetic acid, 3-(meth)acryloxypropionic acid, 4-(meth)acryloxypropionic acid, Oxybutyric acid, acrylic acid dimer, itaconic acid, maleic acid, maleic anhydride or the like.

Examples of nitrogen-containing monomers may include (meth)acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, or the like.

For (meth)acrylate-based resins, at least one of vinyl acetate, styrene, and acrylonitrile may also be further copolymerized for other functional improvements such as compatibility.

In one embodiment of the present application, the acrylate resin can be selected from the group consisting of: alkyl (meth)acrylate, hydroxyalkyl acrylate, and nitrogen-containing monomers.

As a monomer having an alkyl group having 1 to 12 carbon atoms, examples of alkyl acrylate and alkyl methacrylate may include pentyl (meth)acrylate, n-butyl (meth)acrylate , ethyl (meth)acrylate, methyl (meth)acrylate, hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-(meth)acrylate One, two or more types of ethylhexyl, lauryl (meth)acrylate, and decyl (meth)acrylate.

Examples of hydroxyalkyl acrylates may include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 6-hydroxyhexyl acrylate, 8-hydroxyoctyl acrylate, 2-hydroxyalkylene acrylate, ethyl ester, 2-hydroxypropyl acrylate or the like.

An example of the nitrogen-containing monomer may include N-vinyl pyrrolidone (VP).

In one embodiment of the present application, according to (meth)acrylate resin Based on 100 parts by weight, the (meth)acrylate resin may contain 50 to 70 parts by weight of alkyl acrylate, 5 to 40 parts by weight of alkyl methacrylate, 0.1 to 10 parts by weight Nitrogen-containing monomers in parts and hydroxyalkyl acrylates in parts by weight to 30 parts by weight.

Containing 50 to 70 parts by weight of alkyl acrylate, 5 to 40 parts by weight of alkyl methacrylate, 0.1 to 10 parts by weight of nitrogen-containing monomer and 1 to 30 parts by weight The (meth)acrylate resin of hydroxyalkyl acrylate means that alkyl acrylate monomers, alkyl methacrylate monomers, nitrogen-containing monomers, and hydroxyalkyl acrylate monomers are polymerized in the weight ratios mentioned above .

In one embodiment of the present application, based on 100 parts by weight of the (meth)acrylate resin, the (meth)acrylate resin may contain 50 to 70 parts by weight, preferably 55 parts by weight Part to 70 parts by weight and more preferably 60 to 70 parts by weight of alkyl acrylate.

In one embodiment of the present application, based on 100 parts by weight of the (meth)acrylate resin, the (meth)acrylate resin may contain 5 parts by weight to 40 parts by weight, preferably 7 parts by weight 35 parts by weight and more preferably 10 to 30 parts by weight of alkyl methacrylate.

In one embodiment of the present application, based on 100 parts by weight of the (meth)acrylate resin, the (meth)acrylate resin may contain 0.1 to 10 parts by weight, preferably 1 part by weight 10 parts by weight and more preferably 3 parts by weight to 10 parts by weight of nitrogen-containing monomers.

In one embodiment of the present application, based on 100 parts by weight of the (meth)acrylate resin, the (meth)acrylate resin may contain 1 to 30 parts by weight, preferably 5 parts by weight Parts to 25 parts by weight and more preferably 5 parts by weight to 20 Parts by weight of hydroxyalkyl acrylate.

When the (meth)acrylate resin has the above-mentioned composition and content, then excellent variable characteristic characteristics of the adhesive sheet are obtained.

In one embodiment of the present application, the adhesive composition may further include one or more selected from the group consisting of: solvent, dispersant, photoinitiator, thermal initiator, and tackifier agent.

According to one embodiment of the present specification, the crosslinking compound may include one or more types of compounds obtained by esterifying polyhydric alcohols selected from the group consisting of hexanediol di(methyl) Acrylates, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate with 2 to 14 ethylene groups, trimethylolpropane di(meth)acrylate, trimethylolpropane di(meth)acrylate, Methylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, 2-triacryloxymethylethylphthalic acid, with 2 Propylene glycol di(meth)acrylate with 14 propylene groups, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate or acidic modification of dipentaerythritol with α,β-unsaturated carboxylic acid A mixture of penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate (TO-2348, TO-2349 of TOAGOSEI Co., Ltd. as trade names); by adding ( Meth)acrylic acid compounds obtained by addition of compounds containing glycidyl groups, such as trimethylolpropane triglycidyl ether acrylic acid adduct or bisphenol A diglycidyl ether acrylic acid adduct; having hydroxyl or ethylenic unsaturation Bonded compounds and ester compounds of polycarboxylic acids, or adducts with polyisocyanates, such as phthalic acid diester of β-hydroxyethyl (meth)acrylate or β-hydroxyethyl (meth)acrylate Toluene diisocyanate adducts; alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate or (meth)acrylic acid2 - ethyl hexyl ester; and 9,9'-bis[4-(2-acryloxyethoxy)phenyl]fluorene. However, the crosslinking compound is not limited thereto, and general compounds known in the art may be used.

According to an embodiment of this specification, the photoinitiator can be substituted by one, two or more than two substituents selected from the following groups: triazine compounds, biimidazole compounds, acetophenones Compounds, O-acyl oxime compounds, 9-oxothioxanthone (thioxanthone) compounds, phosphine oxide compounds, coumarin compounds and benzophenone compounds.

Specifically, according to an embodiment of this specification, the photoinitiator can use the following compounds alone or a mixture of two or more of the following compounds: triazine compounds, such as 2,4-bis(tri Chloromethyl)-6-(4'-methoxyphenyl)-triazine, 2,4-bis(trichloromethyl)-6-(4'-methoxystyryl)-triazine, 2,4-bis(trichloromethyl)-6-(bisfluorenyl)-triazine, 2,4-bis(trichloromethyl)-6-(3',4'-dimethoxyphenyl )-triazine, 3-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propionic acid, 2,4-bis(trichloromethyl) -6-(4'-ethylbiphenyl)-triazine or 2,4-bis(trichloromethyl)-6-(4'-methylbiphenyl)-triazine; biimidazoles, such as 2 ,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole or 2,2'-bis(2,3-dichlorophenyl)-4,4' ,5,5'-tetraphenylbiimidazole; acetophenones such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)- 2-Hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy)acetone, 1-hydroxycyclohexylbenzophenone, 2,2-dimethoxy -2-phenylacetophenone, 2-methyl-(4-methylthienyl)-2-morpholinyl-1-propan-1-one (Irgacure-907) or 2-benzene Methyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one (Yanjiagu-369); O-acyl oxime compounds, such as Ciba Geigy Co., Ltd. ( Ciba Geigy Ltd.) Yan Jia solid OXE 01 or Yan Jia solid OXE 02; Benzophenone compounds such as 4,4'-bis(dimethylamino)benzophenone or 4,4'-bis( Diethylamino) benzophenone; 9-oxothioxanthenes, such as 2,4-di Ethyl 9-oxothioxanthene, 2-chloro 9-oxothioxanthene, isopropyl 9-oxothioxanthene or diisopropyl 9-oxothioxanthene; phosphine oxides such as 2,4, 6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide or bis( 2,6-dichlorobenzoyl)propylphosphine oxide; coumarins such as 3,3'-carbonylvinyl-7-(diethylamino)coumarin, 3-(2- Benzothiazolyl)-7-(diethylamino)coumarin, 3-benzoyl-7-(diethylamino)coumarin, 3-benzoyl-7-methoxy- Coumarin or 10,10'-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-Cl]-benzopyrano[ 6,7,8-ij]-quinazin-11-one or the like, however, the photocuring agent is not limited thereto.

In addition, those thermal initiators known in the art may be used as thermal initiators.

Toluene may be used as the solvent, however, the solvent is not limited thereto as long as the solvent can dissolve certain materials, and such general-purpose organic solvents may be used.

One embodiment of the present application is directed to providing an adhesive film comprising a base film; and an adhesive sheet comprising an adhesive composition according to an embodiment of the present application disposed on one surface of the base film or its cured material.

The laminated structure of the adhesive film can be recognized in FIG. 1 , and specifically, the adhesive film has a structure in which a base film ( 101 ) and an adhesive sheet ( 102 ) are continuously laminated.

In one embodiment of the present application, the adhesive sheet may contain the adhesive composition actually according to one embodiment of the present application.

In one embodiment of the present application, the adhesive sheet may include a curing material of the adhesive composition according to one embodiment of the present application.

An embodiment of the present application provides an adhesive film, which further includes a release film on the surface of the adhesive sheet opposite to the surface contacting the base film.

A release film refers to a transparent layer attached to one surface of an adhesive sheet as a layer for protecting an extremely thin adhesive sheet, and a hydrophobic film can be used, and a film having excellent mechanical strength, thermal stability, and moisture-proof properties can be used , isotropic, and similar properties. For example, acetate-based (such as triacetylcellulose (TAC)) resin films, polyester-based resin films, polyether-based resin films, polycarbonate-based resin films, polyamide-based resin films, and polyamide-based resin films can be used. Resin film, polyimide-based resin film, polyolefin-based resin film, cycloolefin-based resin film, polyurethane-based resin film, acrylic resin film, and the like, however, the release film is not limited thereto as long as the release film The liner can be a commercially available silicone-treated release film.

In one embodiment of the present application, the base film can be selected from the group consisting of: polyethylene terephthalate (polyethylene terephthalate; PET), polyester, polycarbonate, polyimide ( polyimide; PI), polyethylene naphthalate (polyethylene naphthalate; PEN), polyether ether ketone (polyether ether ketone; PEEK), polyarylate (polyarylate; PAR), polycyclic olefin (polycylic olefin; PCO), Polynorbornene, polyethersulphone (PES) and cycloolefin polymer (cycloolefin polymer; COP).

In another embodiment, the base film may be polyethylene terephthalate (PET).

In one embodiment of the present application, the thickness of the base film may be greater than or equal to 10 microns and less than or equal to 200 microns, preferably greater than or equal to 15 microns and less than or equal to 100 microns, and more preferably greater than or equal to 20 microns and less than or equal to 75 microns.

In addition, the base film is preferably transparent. The base film described herein is transparent means that the light transmittance of visible light (400 nm to 700 nm) is 80% or higher.

When the base film has a thickness within the above-mentioned range, the laminated adhesive film can be prepared as a film.

In one embodiment of the present application, the thickness of the adhesive sheet may be greater than or equal to 3 microns and less than or equal to 100 microns.

In another embodiment, the thickness of the adhesive sheet may be greater than or equal to 3 microns and less than or equal to 100 microns, preferably greater than or equal to 5 microns and less than or equal to 80 microns, and more preferably greater than or equal to 10 microns and Less than or equal to 50 microns.

When the adhesive sheet has a thickness within the above-mentioned range, rework characteristics are excellent when improperly attached, and in particular, no foreign matter remains when the adhesive sheet is removed.

In the adhesive film provided in one embodiment of the present application, the adhesive film has a thickness greater than or equal to 50 micrometers and less than or equal to 300 micrometers.

In another embodiment, the thickness of the adhesive film may be greater than or equal to 50 microns and less than or equal to 300 microns, preferably greater than or equal to 50 microns and less than or equal to 270 microns, and more preferably greater than or equal to 50 microns and Less than or equal to 250 microns.

With an adhesive film having a thickness within the above-mentioned range, when used subsequently in a plastic organic light-emitting display, a proper thickness is obtained as a backplane, and besides that, rework characteristics are excellent when improperly attached Yes, and specifically, no foreign matter remains when the adhesive sheet is removed.

One example of the present application provides an adhesive film in which initial adhesion after being left untreated for 2 hours at 23° C. A strength of 100 gf/inch or less, Intermediate adhesion strength of 110 gf/inch or less after 24 hours untreated at 23°C and post-adhesion strength of 130 gf/inch after 240 hours untreated at 23°C inch or less than 130 gf/inch.

The initial adhesive strength, intermediate adhesive strength and post-adhesive strength were each tested using a texture analyzer (Stable Micro Systems) at an angle of 180° and a peeling rate of 1800 mm/min and using a 2 kg rubber roller to run back and forth once Measured after attaching the adhesive sheet prepared according to the present invention to stainless steel (304 substrate).

In another example, the initial adhesive strength after the surface of the adhesive sheet opposite to the surface contacting the base film is bonded to stainless steel (SUS304 substrate) and left untreated at 23°C for 2 hours may be 100 g/m Inch or less than 100 gf/inch, preferably 95 gf/inch or less, and more preferably 93 gf/inch or less.

In another example, the initial adhesive strength after the surface of the adhesive sheet opposite to the surface contacting the base film is bonded to stainless steel (SUS304 substrate) and left untreated at 23°C for 2 hours may be 5 gf/ Inch or greater than 5 gf/inch, preferably 10 gf/inch or greater, and more preferably 15 gf/inch or greater.

In another example, after bonding the surface of the adhesive sheet opposite to the surface contacting the base film with stainless steel (SUS304 substrate) and leaving it untreated for 24 hours at 23° C., the intermediate adhesive strength may be 110 g/m Inch or less than 110 gf/inch, preferably 105 gf/inch or less, and more preferably 100 gf/inch or less.

In another example, after bonding the surface of the adhesive sheet opposite to the surface contacting the base film with stainless steel (SUS304 substrate) and leaving it untreated for 24 hours at 23° C., the intermediate adhesive strength may be 5 gf/ Inch or greater than 5 gf/inch, preferably 10 gf/inch or greater, and more preferably 15 gf/inch or greater.

In another example, the post-adhesion strength after the surface of the adhesive sheet opposite to the surface contacting the base film is adhered to stainless steel (SUS304 substrate) and left untreated at 23°C for 240 hours may be 130 g/m Inch or less than 130 gram force/inch, preferably 125 gram force/inch or less than 125 gram force/inch, and more preferably 120 gram force/inch or less than 120 gram force/inch.

In another example, the post-adhesive strength after the surface of the adhesive sheet opposite to the surface contacting the base film is adhered to stainless steel (SUS304 substrate) and left untreated at 23°C for 240 hours may be 5 gf/ Inch or greater than 5 gf/inch, preferably 10 gf/inch or greater, and more preferably 15 gf/inch or greater.

Using an adhesive sheet according to the present application comprising a polymer having a melting temperature of 35°C or higher as described above, kept untreated for 2 hours at room temperature (23°C) / kept untreated for 24 Hours/Leaving untreated for 240 hours maintained adhesion strength at a low level.

An embodiment of the present application provides an adhesive film, wherein the late-stage adhesive strength/initial adhesive strength is greater than or equal to 0.9 and less than or equal to 1.8.

In another embodiment, the post-adhesion strength/initial adhesion strength may be greater than or equal to 0.9 and less than or equal to 1.8, preferably greater than or equal to 0.95 and less than or equal to 1.8, and more preferably greater than or equal to 1.0 and less than or equal to 1.78.

In one embodiment of the present application, the adhesive sheet and the base film may be laminated in plural.

In the present application, the adhesive film can be prepared by coating the adhesive composition on the base film using a rod coater.

One embodiment of the present application provides a backsheet film comprising the adhesive film according to the present application; and a protective film disposed on the base film side of the adhesive film.

One embodiment of the present application is directed to providing a backsheet film, which includes the adhesive film according to the present application; and a protective film disposed on one surface of the adhesive film, wherein the adhesive film is formed with a base film and an adhesive sheet, and The protective film is provided on the surface of the base film opposite to the surface contacting the adhesive sheet.

The laminated structure of the backsheet membrane can be identified in Figure 2. Specifically, the back sheet film has a laminated structure of an adhesive film (103) and a protective film (104), and more specifically, the adhesive sheet (103) is formed with a base film (101) and an adhesive sheet (102), and One surface of the base film (101) is bonded to the protective film (104) in the backsheet film (105).

In the backplane film, the protective film performs the role of protecting the adhesive film when transferring the backplane film or performing a process, and the protective film can be removed when the backplane film is used in a plastic OLED later.

In one embodiment of the present application, the protective film may be formed with a protective substrate; and an adhesive layer.

The same material can be used as a base film as a protective base.

The adhesive layer is not limited thereto as long as it can adhere and protect the base and the base film, and a commercially available general-purpose adhesive layer may be used.

An embodiment of the present application provides a plastic organic light-emitting display, which includes the adhesive film according to the present application; a plastic substrate, and an adhesive sheet disposed on the adhesive film side; and the organic light-emitting layer is disposed on the surface of the plastic substrate opposite to the surface contacting the adhesive film.

One embodiment of the present application is aimed at providing a plastic organic light-emitting display, which includes the adhesive film according to the present application; a plastic substrate disposed on one surface of the adhesive film; and an organic light-emitting layer disposed on and in contact with the plastic substrate. On the surface opposite to the surface of the adhesive film, wherein the adhesive film is formed with a base film and an adhesive sheet, and the plastic substrate is arranged on the surface of the adhesive sheet opposite to the surface contacting the base film.

One embodiment of the present application provides a plastic OLED, which includes a protective film disposed on the base film side of the adhesive film.

The laminated structure of the plastic OLED can be identified in FIG. 3 . Specifically, the plastic organic light emitting display has the following lamination structure: protective film (104); adhesive film (103); plastic substrate (106); and organic light emitting layer (107), and more specifically, identifiable adhesive The lamination structure of the adhesive sheet (102) of the film (103) and the plastic organic light-emitting display of the plastic substrate (106).

In the laminated structure of the plastic OLED, the protective film can be removed.

Polyimide (PI) can be used as the plastic substrate.

The organic light-emitting layer can be selected from the group consisting of organic photoelectric devices, organic transistors, organic solar cells, organic light-emitting devices, and micro-LED devices.

Hereinafter, the present disclosure will be described in detail with reference to examples so that those skilled in the art can easily implement the present disclosure. However, the present disclosure can be implemented in various different forms and is not limited to the examples described herein.

<Preparation example>

<Preparation Example 1> Polymerization of (meth)acrylate resin

In ethylhexyl acrylate (ethylhexyl acrylate; EHA)/methyl methacrylate (methyl methacrylate; MMA)/N-vinylpyrrolidone (VP)/hydroxyethyl acrylate (hydroxyethyl acrylate; HEA) at 65/ After introducing ethyl acetate (ethyl acetate; EA) at a weight ratio of 20/5/10, azobisisobutyronitrile (azobisisobutyronitrile; AIBN) (a thermal polymerization initiator) was introduced thereinto to prepare The weight average molecular weight of the (meth)acrylate resin.

<Preparation Example 2> Polymerization of Polymer

After introducing the materials having the composition and weight ratio of the following Table 1 into toluene, azobisisobutyronitrile (AIBN) (a thermal polymerization initiator) was introduced thereinto to prepare the melting temperature (Tm) satisfying the following Table 1 ) and weight average molecular weight polymers.

In Table 1, BMA is butyl methacrylate, STMA is stearyl methacrylate, HDMA is hexadecyl methacrylate, EHMA is ethylhexyl methacrylate, and MMA is methyl methacrylate .

In Table 1, FM0721 is a monofunctional polysiloxane, and a product of Chisso Corporation is used, and FM0721 is a (meth)acrylate monomer in which polysiloxane exists.

In Table 1, BYK-377 is a structure used as a general-purpose additive, and a product of BYK Corporation was used.

FM0721 is a structure containing polymerizable (meth)acrylate and can react with other monomers, however, BYK-377 is a simple additive that cannot be polymerized.

The monomers used in Examples 1 to 3 are monomers having Tm characteristics when polymerized, and the polymers of Comparative Examples 2 to 5 do not have crystallinity, and thus do not show melting temperature behavior and have no Tm value, And the BMA used in Comparative Example 4 also exhibited only Tg but not Tm characteristics, and Tg was approximately 20°C.

<Preparation Example 3> Preparation of Adhesive Composition

With respect to 100 parts by weight of the (meth)acrylate resin prepared in Preparation Example 1, an isocyanate crosslinking agent (Samyoung Ink & Paint Industrial, Co., Ltd. ), DR7030HD), the polymer prepared in Preparation Example 2 in the ratio of parts by weight in Table 2 below was added thereto, and then the product was diluted to have a solid content of 20% using a toluene solution.

On a polyethylene terephthalate (PET) film (T91455) from Mitsubishi Plastics Inc. (MPI) having two surfaces treated with anti-static (AS) The adhesive composition prepared in Example 3 was coated to a thickness of 15 micrometers, and polyethylene terephthalate (PET) (RF12AS) having both surfaces treated with antistatic (AS) was coated thereon. After that, the product was aged at 40° C. for 2 days to prepare an adhesive sheet.

T91455 is an adhesive-coated base film, and FR12AS can be expressed as a release film.

The results of measuring the initial adhesive strength (gram force/inch), intermediate adhesive strength (gram force/inch) and post-stage adhesive strength (gram force/inch) of Examples 1 to 3 and Comparative Examples 1 to 5 are described below Table 3.

1. Initial adhesive strength: The adhesive sheet of one of the films produced in Examples 1 to 3 and Comparative Examples 1 to 5 was laminated with stainless steel (SUS304 substrate) using a 2 kg rubber roller running back and forth once, and the Keep the product at 23 °C without adding After 2 hours of treatment, the adhesion strength was measured using a texture analyzer by peeling the film from stainless steel (SUS304 substrate) at an angle of 180° and a peeling rate of 1800 mm/min.

2. Intermediate adhesive strength: The adhesive sheet of one of the films produced in Examples 1 to 3 and Comparative Examples 1 to 5 was laminated with stainless steel (SUS304 substrate) using a 2 kg rubber roller running back and forth once, and the After the product was left untreated at 23° C. for 24 hours, the adhesion strength was measured by peeling the film from stainless steel (SUS304 substrate) at an angle of 180° and a peeling rate of 1800 mm/min using a texture analyzer.

3. Post-adhesion strength: The adhesive sheet of one of the films produced in Examples 1 to 3 and Comparative Examples 1 to 5 was laminated with stainless steel (SUS304 substrate) using a 2 kg rubber roller running back and forth once, and the After the product was left untreated at 23° C. for 240 hours, the adhesion strength was measured by peeling the film from stainless steel (SUS304 substrate) at an angle of 180° and a peeling rate of 1800 mm/min using a texture analyzer.

As identified in Table 3, the adhesive sheet including the adhesive composition of the present application has the following properties by including a polymer having a melting temperature (Tm) of 35°C or higher and a (meth)acrylate resin. Low initial adhesive strength. Specifically, as identified in Examples 1 to 3, it was recognized that, compared with Comparative Examples 1 to 5, an extremely low initial adhesive strength was maintained.

Specifically, it was recognized that, although having low initial adhesive strength, the adhesive sheets (Examples 1 to 3) of the adhesive film according to one Example of the present application had Maintains constant adhesive strength without increasing even when stored at low temperature for a long period of time. This is achieved by including the Tm row in the adhesive sheet The characteristics obtained for the polymers of the Tg type were identified and the stability over time was found to be excellent compared to when Tg type polymers were included.

In Comparative Example 1, it was recognized that stability over time was obtained without significant difference in adhesive strength as in the present disclosure, however, in the process of removing the adhesive sheet due to higher initial adhesive strength Foreign matter, or rework characteristics are not favorable compared to the adhesive sheet of the present application.

In Comparative Examples 2 to 5, it was recognized that low initial adhesive strength was maintained, however, adhesive strength increased upon long-term storage at room temperature, and thus, foreign substances were generated during the removal process.

In addition, Examples 1 to 3 include 1 to 10 parts by weight of a polymer having a melting temperature of 35° C. or higher with respect to 100 parts by weight of the (meth)acrylate resin, and at room temperature It has excellent stability over time, and when the (meth)acrylate resin is not further contained, it is seen that it is difficult to form an adhesive sheet.

Specifically, in order to obtain active bending, a part of the panel of the plastic organic light-emitting diode (POLED) needs to have a process for removing the adhesive sheet, and the backplane film including the adhesive sheet according to the present application can be obtained by having The characteristics of low initial adhesive strength to prevent damage to the panel are also maintained during long-term storage at low temperature, and it was recognized that the backsheet film according to the present application is suitable.

101: Basement Membrane

102: Adhesive sheet

103: Adhesive film

Claims (13)

An adhesive composition comprising: (meth)acrylate resin; and a polymer having a melting temperature (Tm) of 35°C to 44°C, wherein the polymer is monofunctional polysiloxane and a type of A copolymer of monomers, wherein based on 100 parts by weight of the (meth)acrylic resin, the adhesive composition contains 1 to 10 parts by weight of a compound having a melting temperature of 35° C. to 44° C. The polymer, wherein, based on 100 parts by weight of the polymer having a melting temperature of 35°C to 44°C, the polymer having a melting temperature of 35°C to 44°C contains 10 parts by weight or more and less than or equal to 40 parts by weight of monofunctional polysiloxane and greater than or equal to 60 parts by weight and less than or equal to 90 parts by weight of the monomer, the polymer having a melting temperature of 35°C to 44°C has 30,000 g/mol to 100,000 g/mol weight average molecular weight, wherein the monomer is represented by the following chemical formula 1:

In Chemical Formula 1, X is N or O; R ₁ is hydrogen or methyl; and n is an integer of 10 to 30. The adhesive composition as described in claim 1, wherein n is an integer from 16 to 22. The adhesive composition as described in claim 1, wherein the monomer represented by Chemical Formula 1 is stearyl methacrylate (stearyl methacrylate; STMA). The adhesive composition described in item 1 of the scope of the patent application further includes one or more selected from the group consisting of: solvent, dispersant, photoinitiator, thermal initiator and tackifier agent. An adhesive film, comprising: a base film; and an adhesive sheet, comprising an adhesive composition as described in any one of items 1 to 4 of the scope of the patent application or its curing on one surface of the base film Material. The adhesive film described in claim 5 of the patent application further includes a release film on the surface of the adhesive sheet opposite to the surface contacting the base film. The adhesive film according to claim 5, wherein after the surface of the adhesive sheet opposite to the surface contacting the base film is bonded to stainless steel (SUS304 substrate), it is left untreated at 23°C for 2 an initial adhesion strength of 100 gf/inch or less after one hour; an intermediate adhesion strength of 110 gf/inch or less after being left untreated for 24 hours at 23°C; and The post-adhesion strength after being left untreated for 240 hours at 23°C was 130 gf/inch or less. The adhesive film as described in item 7 of the patent application, wherein the late-stage adhesive strength/the initial adhesive strength is greater than or equal to 0.9 and less than or equal to 1.8. The adhesive film as described in claim 5 of the patent application, wherein the adhesive sheet has a thickness greater than or equal to 3 microns and less than or equal to 100 microns. The adhesive film described in claim 5 of the patent application has a thickness greater than or equal to 50 microns and less than or equal to 300 microns. A backsheet film comprising: the adhesive film described in claim 7 of the patent application; and a protective film disposed on the base film side of the adhesive film. A plastic organic light-emitting display, comprising: the adhesive film as described in item 5 of the scope of the patent application; a plastic substrate disposed on the side of the adhesive sheet of the adhesive film; and an organic light-emitting layer disposed on the plastic substrate and on the surface opposite to the surface that contacts the adhesive film. The plastic organic light emitting display as described in claim 12 of the patent application includes a protective film, and the protective film is disposed on the base film side of the adhesive film.

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